That includes all versions for characters like Ratchet and Ultra Magnus, G1, Animated, etc.

Bad: Skywarp, Thundercracker, Megatron/Galvatron, in all forms and variations, Soundwave, Terrorcons, RiD Scourge, all RiD Decepticons and Predacons really, all the "Victory" Decepticons/Destrons, "Prime" Knock Out and his distant ancestor Terrorsaur...

..many others I'm sure I'm leaving out.

The characters that I actually make a point to buy as many different figures of as possible are Ultra Magnus, Megatron, Bumblebee and Hot Rod/Rodimus.